• Journal of Engineering Education Research
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• v.2 no.1
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• pp.39-50
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• 1999

In recent globalization era, Korean architectural education and profession are emerging as the fields with serious problems. There are two major reasons. One is an internal factor caused by Ministry of Education's full scale shift from department to faculty system. Due to the drastic change in this system, most of schools have serious difficulties to deliver the proper professional education. And the other is an external factor. In WTO era, Union of International Architects has adopted $\ulcorner$UIA Accord on Recommended International Standards of Professionalism In Architectural Practice$\lrcorner$. According to the education section of the Accord, it requires 5 years of professional education in the accredited school. So, if it is formally adopted in the Beijing Congress, which is scheduled to be held in June 1999, we may face very serious problems in architectural education. As mentioned above, with the present education system it is believed not easy to meet their new criteria. Within the present system, which does not have any mandatory relationship with professional licence, students might go on to diverse fields such as architectural design, structural engineering, construction management and building equipment engineering. However, if UIA Accord and Engineering Accreditation are required at the same time, it will not be easy to meet their new criteria with present architectural education system. The goal of this paper is to suggest the models to meet the standards of international community while keeping the strengths of existing systems.

• Journal of Korea Water Resources Association
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• v.50 no.2
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• pp.75-87
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• 2017

In recent decades, extreme events have been significantly increased over the Korean Peninsula due to climate variability and climate change. The potential changes in hydrologic cycle associated with the extreme events increase uncertainty in water resources planning and designing. For these reasons, a reliable changing point analysis is generally required to better understand regime changes in hydrologic time series at watershed scale. In this study, a hierarchical changing point analysis approach that can apply in a watershed scale is developed by combining the existing changing point analysis method and hierarchical Bayesian method. The proposed model was applied to the selected stations that have annual rainfall data longer than 40 years. The results showed that the proposed model can quantitatively detect the shift in precipitation in the middle of 1990s and identify the increase in annual precipitation compared to the several decades prior to the 1990s. Finally, we explored the changes in precipitation and sea level pressure in the context of large-scale climate anomalies using reanalysis data, for a given change point. It was concluded that the identified large-scale patterns were substantially different from each other.

• Journal of the Korean association of regional geographers
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• v.4 no.2
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• pp.201-217
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• 1998

This paper examined the strategy of experiential learning on Web-based cyberspace for constructive education of social studies. The results as follows : The first, constructivism has brought the paradigm shift in traditional principles of teaching and learning, constructivism is not a theory about teaching, it is a theory about knowledge and learning, learning is understood as a self-regulated process of resolving inner cognitive conflicts that often become apparent through experience, collaborative discourse, and reflection. It is proper for constructive education of social studies to carry out from cognitive constructivism to socio-cultural constructivism, from socio-cultural constructivism to cognitive constructivism and co-constructivism, considering the aim or objectives of social studies education. The second, Web-based Instruction(WBI) can provide learners for constructive environments which can be proper for teaching and learning. WBI was suggested as the best medium for constructive education of social studies in the information age. WBI must design teaching and learning so that may not be teacher-centered, if teacher-centered, it is not constructivism. The third, Web-based cyberspace is the proper mediated experience fields for experiential learning to effectively study regions or space because of overcoming distance fractions through the time-space convergence, it actualize the constructive education of social studies in the space age.

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.2
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• pp.103-110
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• 2010

In this paper, a new mode changeable asymmetric full bridge dc/dc converter is proposed to solve the freewheeling current problem of the conventional zero voltage switching(ZVS) phase shift full bridge(PSFB) dc/dc converter of low output voltage and high output current applications. The proposed converter is operated as an asymmetric full bridge converter when the duty cycle is less than 50% and active clamp full bridge converter when the duty cycle is greater than 50%. As a result, since its freewheeling current is eliminated, the conduction loss is lower than that of the conventional ZVS PSFB dc/dc converter. Moreover, ZVS of all power switches can be ensured along a wide load ranges and output current ripple is very small. Therefore, high efficiency of the proposed converter can be achieved. Especially since its operation mode is changed to the active clamp full bridge converter during hold up time and can be operated with 50~100% duty ratio, it can produce the stable output voltage along wide input voltage range. The operational principles, theoretical analysis and design considerations are presented. To confirm the operation, validity and features of the proposed converter, experimental results from a 1.2kW($400V_{dc}/12V_{dc}$) prototype are presented.

• The Journal of the Acoustical Society of Korea
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• v.40 no.5
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• pp.479-487
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• 2021

In this paper, we propose an Sound Event Detection (SED) model using self-training based on a noisy student model. The proposed SED model consists of two stages. In the first stage, a mean-teacher model based on an Residual Convolutional Recurrent Neural Network (RCRNN) is constructed to provide target labels regarding weakly labeled or unlabeled data. In the second stage, a self-training-based noisy student model is constructed by applying different noise types. That is, feature noises, such as time-frequency shift, mixup, SpecAugment, and dropout-based model noise are used here. In addition, a semi-supervised loss function is applied to train the noisy student model, which acts as label noise injection. The performance of the proposed SED model is evaluated on the validation set of the Detection and Classification of Acoustic Scenes and Events (DCASE) 2020 Challenge Task 4. The experiments show that the single model and ensemble model of the proposed SED based on the noisy student model improve F1-score by 4.6 % and 3.4 % compared to the top-ranked model in DCASE 2020 challenge Task 4, respectively.

• The Journal of Korean Philosophical History
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• no.58
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• pp.139-160
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• 2018

'Gyeokmulchiji' (格物致知), coming to knowledge based on the investigation of things) is a starting point for any study and politics of Confucianism. Much emphasis was placed on the conception of 'Gyeokchi' as a root of every learning and adminstration in the early Joseon period. As Confucianism established itself as a salient value system of the government, a mighty change and paradigm shift happened in its governmental system which had depended upon Buddhism up to that time. Thus, Confucian statecraft also stood out. Daehakyeonui (大學衍義) was preached as a model of regal learning and politics in the governmental agon, and its conceptual starting point was 'Gyeokchi.' The various interpretations and arguments about this concept shows the process in which Zhu Xi NeoConfucianism was deepened into Neo-Confucianism of Joseon's own. This conception reached the essence of 'Li' beyond the problem of cognitive subject and object, and provided a watershed which divided Giho (畿湖) and Yeongnam (嶺南) schools. Confucian method of study, which incorporates knowledge and practice, has great implications for our times when there are many voices of concern over humanities. The enhancement of universities and humanities is much needed to adjust the direction and pace of scientific technology, which is now entirely left with the logic of market. Accordingly, it is quite urgent for us to examine our object of learning again, which should integrate 'Sugi' (修己, cultivating oneself) with 'Chi-in' (治人, governing others), and knowledge with practice.

• Development and Reproduction
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• v.16 no.3
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• pp.227-233
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• 2012

Circadian timing system plays a major role in a wide range of reproductive function. However it is plausible idea that other environmental and/or internal cue might be simultaneously participated in the optimal regulation of reproductive system. In the present study we extended the reverse feeding (RF) time regimen up to 8 weeks, then measured the general and reproductive indices of the animals. The animals of ad libitum feeding group (Control, CON) have free access to food for 4, 6 and 8 weeks, respectively. The day feeding animals (reverse feeding, RF group) have restricted access to food during daytime (09:00-18:00) for 4, 6 and 8 weeks, respectively. When the feeding schedules were over, key indices were measured. After 4 weeks and 8 weeks of feeding, body weights of animals were not significantly different. However, body weights of 6 weeks RF animals were significantly smaller than those of control animals (CON : RF = $333.46{\pm}12.71$ g : $289.91{\pm}8.31$ g, p<0.01). The blood glucose levels of 4 weeks RF animals were significantly decreased compared to the levels of control animals (CON : RF = $161.4{\pm}2.7$ mg/dL : $176.7{\pm}5$ mg/dL, p<0.01) while the levels of 6 weeks RF and 8 weeks RF animals were not different form those of control animals. Reproductive and non-reproductive tissue weights from 6 weeks RF group were significantly lowered than those from CON group (testis, CON : RF = $1.4714{\pm}0.0174$ g : $1.3724{\pm}0.0168$ g, p<0.001; epididymis, CON : RF = $0.3574{\pm}0.0059$ g : $0.3243{\pm}0.0068$ g, p<0.001; seminal vesicle, CON : RF = $0.1655{\pm}0.0068$ g : $0.1328{\pm}0.0054$ g, p<0.001; prostate, CON : RF = $0.3350{\pm}0.0231$ g : $0.2528{\pm}0.0143$ g, p<0.01). After 4 weeks and 8 weeks of reverse feeding, sperm counts in RF animals were markedly reduced than those in control animals[CON 4W : RF 4W = $121.17{\pm}9.96\;({\times}10^6)$ : $50.86{\pm}9\;({\times}10^6)$, p<0.001; CON 8W : RF 8W= $138.69{\pm}9.8\;({\times}10^6)$ : $108.94{\pm}4.22\;({\times}10^6)$, p<0.001]. Present study indicates that RF may induce an adaptable metabolic stress and cause impairment of androgen-dependent reproductive tissues. On-going longitudinal studies will allow a better understanding of the how does mealtime shift affect the reproductive function and exact nature of adaptation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.5
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• pp.1125-1134
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• 2011

In this paper a wideband frequency synthesizer is designed for DTV tuners using a $0.18{\mu}m$ CMOS process. It satisfies the DTV frequency band(48~1675MHz). A scheme is proposed to cover the full band using only one VCO and reliable broadband characteristics are achieved by reducing the variations of VCO gains and frequency steps. The simulation results show that the designed VCO has frequency range of 1.85~4.22GHz, phase noise at 4.22GHz of -89.7dBc/Hz@100kHz, gains of 62.4~95.8MHz/V(${\pm}21.0%$) and frequency steps of 22.9~47.9MHz(${\pm}35.3%$). The designed VCO has a phase noise of -89.75dBc/Hz at 100kHz offset. The designed synthesizer has a lock time less than $0.15{\mu}s$. The measured VCO tuning range is 2.05~3.4GHz. The frequency range is shifted down but still satisfy the target range owing to the design for enough margin. The designed circuit consumes 23~27mA from a 1.8V supply, and the chip size including PADs is $2.0mm{\times}1.5mm$.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.4
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• pp.277-285
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• 2022

To investigate the adverse effects of clozapine on cardiovascular ion channels, we examined the inhibitory effect of clozapine on voltage-dependent K⁺ (Kv) channels in rabbit coronary arterial smooth muscle cells. Clozapine-induced inhibition of Kv channels occurred in a concentration-dependent manner with an half-inhibitory concentration value of 7.84 ± 4.86 µM and a Hill coefficient of 0.47 ± 0.06. Clozapine did not shift the steady-state activation or inactivation curves, suggesting that it inhibited Kv channels regardless of gating properties. Application of train pulses (1 and 2 Hz) progressively augmented the clozapine-induced inhibition of Kv channels in the presence of the drug. Furthermore, the recovery time constant from inactivation was increased in the presence of clozapine, suggesting that clozapine-induced inhibition of Kv channels is use (state)-dependent. Pretreatment of a Kv1.5 subtype inhibitor decreased the Kv current amplitudes, but additional application of clozapine did not further inhibit the Kv current. Pretreatment with Kv2.1 or Kv7 subtype inhibitors partially blocked the inhibitory effect of clozapine. Based on these results, we conclude that clozapine inhibits arterial Kv channels in a concentration-and use (state)-dependent manner. Kv1.5 is the major subtype involved in clozapine-induced inhibition of Kv channels, and Kv2.1 and Kv7 subtypes are partially involved.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.165-173
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• 2024

Restoring lost teeth is very important in terms of both function and aesthetics. If tooth loss occurs in the posterior region and the loss of support is persistent, it may cause a gradual shift in the position of the mandible and a change in occlusion. This clinical case attempted to restore support for the posterior teeth with a fixed prosthesis using implants in a patient whose opposing teeth were erupted and the occlusal plane collapsed due to long-term loss of the maxillary left posterior teeth and mandibular right first molars. To correct the occlusal plane of remaining dentition, wax-up of maxillary left posterior teeth was duplicated with acrylic resin and placed on maxilla. Surgical template for implant placement were fabricated using digital technology. After the support of the posterior teeth was restored with the placement of the implant, stable occlusion with temporary restorations was observed for a sufficient time. Afterwards, monolithic zirconia prosthesis was placed on the patient to ensure functional and aesthetic improvement.